The present invention is concerning a fastening arrangement for a circular tool arrangement which is designed so that the circular arrangement can be shifted laterally around a rotatable shaft carrying at least one of the circular tool arrangements.
Processing machines are known which have circular tool arrangements which support tools having a form of an annular sector and the circular tool arrangement is shiftable with respect to a shaft that carries the tool arrangement. Thus, it is possible to convert a sheet of material, such as a sheet of paper board or a corrugated board, into blanks by passing the sheet through the machine so that the tools of the circular tool arrangement can perform a process on the board; which is cutting if they are cutting tools and creasing if they are creasing tools. Generally, such machines include an upper rotary shaft supporting the circular tool arrangements and a lower rotary shaft carrying the circular counterparts which are situated opposite the circular tool arrangements and have grooves for coacting with the tool portions of the tool arrangement. The cutting and creasing tools will generally be called cutting or creasing members.
Such cutting and creasing members operate jointly with the countermember situated on the circumference of the circular counterparts and which are fitted on the lower rotary shaft. The tools can be designed to make slots, diagonal corner cuts and creases on the paper board or corrugated sheets which runs between the cutting and creasing members and the countermember.
As mentioned above, the members are shiftable angularly on the circumference of the circular tool arrangement and it is possible, for instance with two non-adjacent cutting members, to achieve two cuts with every revolution of the rotary shaft, for example a cut adjacent the front or leading edge and a cut adjacent the rear or trailing edge of the sheet of material being processed.
In order to be able to consider the length of the sheet to be converted, it is useful to arrange on the circumference of the circular tool arrangement at least a first fixed cutting member and a second cutting member which can be adjustable with regard to its angular position. In order to take into account the width of the sheet to be converted, several circular apparatuses provided with cutting and creasing members are to be arranged side-by-side on the same rotary shaft. Thus, a sheet can be processed into a blank which has several panels with several flaps, such as the blank illustrated in U.S. Pat. No. 3,985,066, whose disclosure is incorporated by reference thereto.
On known devices, the shiftable members or adjustable members are secured on an inner rim which has teeth along one periphery. To enable a simultaneous setting of all the shiftable or adjustable members of several of the circular tool arrangements located side-by-side, a shaft extends between each of the tool arrangements and includes a pinion for each arrangement that engages the inner rim in such a way that the inner rims of each arrangement can be simultaneously shifted to present a new angular position for the member mounted thereon.
Conspicuously, the above-mentioned cutting members undergo appreciable wear when converting material. Furthermore, they can be worn or damaged, for instance, by the wrong manipulation or by a sudden jam-up. There is also a risk of the cutting members interfering in that it might prevent the obtaining of a certain slot dimension. In the above-mentioned cases, it will, thus, be necessary to remove one or the other of the cutting members carried by a circular tool arrangement. Such a removable operation should obviously be carried out quickly and easily so that the machine will be down during the shortest time possible in order that the machine's production capacity is not impaired.
The fastening devices of the cutting members, as known up to now, hold the cutting members by means of retaining elements on which the cutting members are fitted by means of screws or expensive and complex couplings which are not very reliable. Such an arrangement is disclosed in the above-mentioned U.S. Patent.